[gentoo-dev] New metadata fields

[Steve Dibb]

I had an idea for some new fields to go in metadata.xml.  Not sure if we 
would need a GLEP for this or not?  Anyway, what do you guys think:

Two things I can think of adding that would be useful:
- ChangeLog URL
- Bug Tracker

I know I hate hunting down the two of them, and both of them could be 
useful references for developers and users.

Plus, not every upstream has them, so they can of course be optional fields.

Steve